Improvement In VO2max Research Articles

Mechanisms Underlying Absent Training-Induced Improvement in Insulin Action in Lean, Hyperandrogenic Women With Polycystic Ovary Syndrome.

Women with polycystic ovary syndrome (PCOS) have been shown to be less insulin sensitive compared with control (CON) women, independent of BMI. Training is associated with molecular adaptations in skeletal muscle, improving glucose uptake and metabolism in both healthy individuals and patients with type 2 diabetes. In the current study, lean hyperandrogenic women with PCOS (n = 9) and healthy CON women (n = 9) completed 14 weeks of controlled and supervised exercise training. In CON, the training intervention increased whole-body insulin action by 26% and insulin-stimulated leg glucose uptake by 53% together with increased insulin-stimulated leg blood flow and a more oxidative muscle fiber type distribution. In PCOS, no such changes were found, despite similar training intensity and improvements in VO2max In skeletal muscle of CON but not PCOS, training increased GLUT4 and HKII mRNA and protein expressions. These data suggest that the impaired increase in whole-body insulin action in women with PCOS with training is caused by an impaired ability to upregulate key glucose-handling proteins for insulin-stimulated glucose uptake in skeletal muscle and insulin-stimulated leg blood flow. Still, other important benefits of exercise training appeared in women with PCOS, including an improvement of the hyperandrogenic state.

Effect of carbohydrate\u2013protein supplementation on endurance training adaptations

PurposeTo examine the influence of post-exercise protein feeding upon the adaptive response to endurance exercise training.MethodsIn a randomised parallel group design, 25 healthy men and women completed 6 weeks of endurance exercise training by running on a treadmill for 30–60 min at 70–75% maximal oxygen uptake (VO2max) 4 times/week. Participants ingested 1.6 g per kilogram of body mass (g kg BM−1) of carbohydrate (CHO) or an isocaloric carbohydrate–protein solution (CHO-P; 0.8 g carbohydrate kg BM−1 + 0.8 g protein kg BM−1) immediately and 1 h post-exercise. Expired gas, blood and muscle biopsy samples were taken at baseline and follow-up.ResultsExercise training improved VO2max in both groups (p ≤ 0.001), but this increment was not different between groups either in absolute terms or relative to body mass (0.2 ± 0.2 L min−1 and 3.0 ± 2 mL kg−1 min−1, respectively). No change occurred in plasma albumin concentration from baseline to follow-up with CHO-P (4.18 ± 0.18 to 4.23 ± 0.17 g dL−1) or CHO (4.17 ± 0.17 to 4.12 ± 0.22 g dL−1; interaction: p > 0.05). Mechanistic target of rapamycin (mTOR) gene expression was up-regulated in CHO-P (+ 46%; p = 0.025) relative to CHO (+ 4%) following exercise training.ConclusionPost-exercise protein supplementation up-regulated the expression of mTOR in skeletal muscle over 6 weeks of endurance exercise training. However, the magnitude of improvement in VO2max was similar between groups.

High intensity interval training increases the utilization of fatty acids in subjects with overweight or obesity. A randomized study

Introduction: the effect of high intensity interval training (HIIT) on fat utilization during exercise needs to be studied in depth. Objective: to determine the effect of HIIT training program in subjects with overweight or obesity on the use of fat during exercise, body composition and cardiovascular variables. The second objective was to compare the variables according to the duration of the program (i.e., 12, 16 and 20 weeks). Material and methods: 30 subjects were studied (age 44.8 ± 11.6 years). Three groups were formed at random, the G1 (12 weeks, n = 12, 48.08 ± 8.20 years), G2 (16 weeks, n = 10, 42.10 ± 11.60 years) and G3 (20 weeks, n = 8, 43.38 ± 15.76 years). All groups performed HIIT 3 times per week. Results: the three groups showed a significant decrease in body fat percentage (p < 0.05), without differences between groups. Similarly, cardiovascular variables did not report differences between groups (p-interaction > 0.05) after the intervention; however, the groups reported a significant decrease systolic blood pressure (p < 0, 05). In the pre vs. post analysis by groups, the three groups showed improvements in VO2max without differences between groups (p-interaction > 0.05). Finally, the three groups increased the fats utilization during exercise (p < 0.05). Conclusion: the program increased fat utilization during exercise, decreased body fat % and improved cardiovascular parameters, however after 12 training weeks it is advisable to apply variations to training to maximize results.

Effects Of High-Intensity Interval Training On Cardiometabolic Risk Factors And Motivation To Exercise In Women With Abdominal Obesity

There has been recent interest in high-intensity interval training (HIIT) as an alternative to moderate-intensity continuous training (MICT) to reduce body composition, adiposity and cardiometabolic risk factors in obese patients. Despite the promising evidence supporting HIIT in this population, there is limited research targeting women with abdominal obesity. PURPOSE: The objective of this study was to compare the effects of MICT and energy-matched HIIT on cardiometabolic risk factors in women characterized by abdominal obesity. METHODS: Twenty abdominally obese women (age range, 28-56 years) were submitted to 12 weeks of intervention and were randomly allocated into 2 groups: MICT (n=10) and HIIT (n=10). The MICT group performed a 38 to 62-minute continuous exercise at 70 % of the maximal heart rate. The HIIT group training performed 3 to 6 sets of 4-minute bouts at a running velocity corresponding to 90 % maximal heart rate, interspersed by a 4-min active recovery period at 50 % maximal heart rate. Anthropometric parameters, maximal oxygen uptake (VO2max) and cardiometabolic risk variables were measured at the beginning and after 12 weeks. Self-determined motivation toward physical activity was also evaluated with a validated questionnaire. RESULTS: MICT intervention led to significant improvements in VO2max (29.9 to 32.7 ml O2*kg-1*min-1, p=0.005), with no change in HIIT group. However, at the beginning of the study, VO2max was significantly lower in the MICT group when compared to the HIIT group (p=0.04). During the intervention, no significant difference was found in cardiometabolic risk factors in the MICT group. However, HIIT resulted in statistically significant reduction in triglycerides levels (1.91 to 1.58 mmol/l, p=0,046) even though waist circumference was significantly increased (98.0 to 100.7 cm, p=0.038) after the 12-week intervention program. In addition, the HIIT group increased self-determined motivation toward physical activity in a greater magnitude when compared with the MICT group (p=0.016). CONCLUSION: HIIT appears to provide greater benefits to MICT for improving triglyceride levels. In addition, as HIIT is associated with a greater improvement in self-determined motivation toward physical activity, HIIT could be associated with promising long-term adherence to exercise.

The Effects of Short-Term High-Intensity Interval Training and Moderate Intensity Continuous Training on Body Fat Percentage, Abdominal Circumference, BMI and VO2max in Overweight Subjects.

We aimed to compare the effects of a personalized short-term high-intensity interval training (HIIT) vs. standard moderate intensity continuous training (MICT) on body fat percentage, abdominal circumference, BMI and maximal oxygen uptake (VO2max) in overweight volunteers. Twenty overweight sedentary volunteers (24.9 ± 2.9y; BMI: 26.1 ± 1 kgm−2) were randomly assigned to 2 groups, HIIT or MICT. HIIT trained 6 weeks (3-days/week), 40-min sessions as follows: 6-min warm-up, 20-min resistance training (RT) at 70% 1-RM, 8-min HIIT up to 90% of the predicted Maximal Heart Rate (HRmax), 6-min cool-down. MICT trained 6 weeks (3-days/week) 60-min sessions as follows: 6-min warm-up, 20-min RT at 70% 1-RM, 30-min MICT at 60–70% of the predicted HRmax, 4-min cool-down. Two-way ANOVA was performed in order to compare the efficacy of HIIT and MICT protocols, and no significant interaction between training x time was evidenced (p > 0.05), indicating similar effects of both protocols on all parameters analyzed. Interestingly, the comparison of Δ mean percentage revealed an improvement in VO2max (p = 0.05) together with a positive trend in the reduction of fat mass percentage (p = 0.06) in HIIT compared to MICT protocol. In conclusion, 6 weeks of personalized HIIT, with reduced training time (40 vs. 60 min)/session and volume of training/week, improved VO2max and reduced fat mass percentage more effectively compared to MICT. These positive results encourage us to test this training in a larger population.

The effect of low-volume high-intensity interval training on cardiometabolic health and psychological responses in overweight/obese middle-aged men

ABSTRACT High-intensity interval training (HIIT) has been proposed as a time-efficient exercise protocol to improve metabolic health, but direct comparisons with higher-volume moderate-intensity continuous training (MICT) under unsupervised settings are limited. This study compared low-volume HIIT and higher-volume MICT interventions on cardiometabolic and psychological responses in overweight/obese middle-aged men. Twenty-four participants (age: 48.1±5.2yr; BMI: 25.8±2.3kg·m−2) were randomly assigned to undertake either HIIT (10 X 1-min bouts of running at 80–90% HRmax separated by 1-min active recovery) or MICT (50-min continuous jogging/brisk walking at 65–70% HRmax) for 3 sessions/week for 8 weeks (2-week supervised + 6-week unsupervised training). Both groups showed similar cardiovascular fitness (VO2max) improvement (HIIT: 32.5±5.6 to 36.0±6.2; MICT: 34.3±6.0 to 38.2±5.1mL kg−1 min−1, p < 0.05) and %fat loss (HIIT: 24.5±3.4 to 23.2±3.5%; MICT: 23.0±4.3 to 21.5±4.1%, p< 0.05) over the 8-week intervention. Compared to baseline, MICT significantly decreased weight and waist circumference. No significant group differences were observed for blood pressure and cardiometabolic blood markers such as lipid profiles, fasting glucose and glycated haemoglobin. Both groups showed similar enjoyment levels and high unsupervised adherence rates (>90%). Our findings suggest that low-volume HIIT can elicit a similar improvement of cardiovascular fitness as traditional higher-volume MICT in overweight/obese middle-aged men.

692-P: Hyperglycemia Impairs Aerobic Adaptation to Exercise

Improved aerobic exercise capacity (VO2max) has emerged as one of the most important health benefits of aerobic exercise training. However, hyperglycemia is associated with low VO2max in humans, even when physical activity levels are matched. To determine how glycemia influences aerobic adaptations with exercise training, we induced moderate hyperglycemia (+50-70 mg/dL vs. control) in mouse models that mimic the pathologies of type 1 or type 2 diabetes: 1) Low-dose Streptozotocin treatment (STZ), or 2) Western diet (WD) feeding. Normoglycemic mice acted as controls (CON). All mice completed ∼500 km of voluntary wheel running over an 8-wk aerobic training period, and achieved the expected metabolic benefits from exercise training. However, metabolic improvements were uncoupled from aerobic adaptation in hyperglycemic WD and STZ mice, who failed to improve VO2max beyond the level of sedentary controls. In contrast, CON mice had a 2-fold increase in VO2max in response to the same training intervention. In hyperglycemic models, blunted improvements in VO2max were associated with structural changes to muscle, including glucose-induced modifications to the extracellular matrix (e.g., glycation and collagen accretion), and reduced exercise-induced angiogenesis and oxidative fiber-type shifts. Thus, our data provide evidence that aerobic muscle remodeling, which is critical for augmenting VO2max, is impaired by hyperglycemia. In addition, we show that chronic hyperglycemia causes hyper-activation of a JNK/SMAD2 signaling network in muscle with acute aerobic exercise, which is a known molecular mechanism that inhibits aerobic adaptation. Accordingly, in human subjects, we show that impaired glucose tolerance strongly predicts hyper-activation of this inhibitory signaling network in conjunction with low VO2max. Taken together, we demonstrate that hyperglycemia, regardless of etiology, may interfere with fundamental adaptations to aerobic exercise training and negatively regulate improvements in VO2max. Disclosure T. MacDonald: None. P. Pathak: None. N.M. Fernandez: None. E.C. Freitas: None. S. Hafida: None. J. Mitri: Consultant; Spouse/Partner; Janssen Pharmaceuticals, Inc., kymera. Consultant; Self; national dairy council/local dairy council. Research Support; Spouse/Partner; AbbVie Inc., beigene, Janssen Pharmaceuticals, Inc. Research Support; Self; Kowa Pharmaceuticals America, Inc., national dairy council. Research Support; Spouse/Partner; pharma cyclic, TG therapeutics. S.J. Lessard: None. Funding American Heart Association (19POST34381036)

163-OR: Metabolically Unhealthy Obese Is Transient and Improves with Aerobic Exercise

Introduction: A subset of adults with obesity may be classified as having metabolically healthy obesity (MHO). There is a high conversion rate from the MHO condition to a metabolically unhealthy obesity (MUO) condition over time. The insulin sensitizing effects of exercise across these metabolic states has not been established and may inform more precise obesity treatment. Methods: Sedentary adults (n=43) with obesity, but not diabetes, underwent inpatient testing (anthropometric measurements, blood chemistries, aerobic capacity (VO2MAX), and insulin sensitivity (euglycemic clamp) before and after 12 weeks of aerobic exercise training (5x/week, 60 min/session, ∼85% HRMAX). A metabolic health score (MetScore) was calculated using baseline values (BMI, VO2MAX, HOMA-IR, triglycerides, and cholesterol) to stratify participants with MHO (n= 21; MetScore ≤ 237) or MUO (n=22; MetScore &amp;gt; 237). Linear mixed models determined group differences over time. Results: MHO and MUO groups differed by MetScore at baseline (202 and 325; P&amp;lt;0.01) and after 12 weeks of exercise (181 and 261; P&amp;lt;0.01), but MHO had lower fasting glucose, insulin, HOMA-IR, and higher HDL-C along with superior M/I, than MUO participants. MetScore improved in the group with MUO (-64; P&amp;lt;0.01) compared to MHO (-20; p=0.06)(P&amp;lt;0.01, between groups). Both groups (MHO v. MUO) experienced similar improvements in VO2MAX (+6.8 and +9.3 ml/kg/min), body weight (-8.8 and -7.5 kg), body fat (-4.2 and -2.9%), triglyceride concentrations (-31.7 and -25.8 mg/dl), and M/I (0.0183 and 0.0166 mg/kg/min/μU/ml) (P&amp;gt;0.20, all between groups). Insulin (-2.62 μU/ml; P=0.0185) and HOMA-IR (-0.71; P=0.022) decreased in the group with MUO with no between group differences (P=0.75 and P=0.52, respectively). Conclusion: Aerobic exercise enhances individual components of health similarly in persons with MHO and MUO after 12 weeks. However, those with MUO experienced the greatest collective improvement, thus presenting an opportunity for intervention. Disclosure K.K. Hoddy: None. C.L. Axelrod: None. J.T. Mey: None. A. Hari: None. R.A. Beyl: None. J.P. Kirwan: None. Funding National Institute on Aging (AG012834); National Institute of General Medical Sciences (GM104940); Louisiana Clinical &amp; Translational Science Center (U54-GM104940)

Interval and Continuous Training for Resting Pulse and Cardiovascular Enhancement of Students

Basketball games are played for 40 minutes divided into 4 quarters, where one quarter is 10 minutes. To play the game of basketball requires having excellent stamina which can be seen from the value of VO₂ Max. There are various types of exercises to improve VO₂ Max, such as interval training and continuous training. The purpose of this study: is to determine the difference in effect between interval training and continuous training on VO₂ Max on basketball players in extracurricular students at Senior high school 2nd Pasuruan City. Research methods: This study used the Pre and Post Test two Groups Design design, with a sample of 12 basketball players as an interval training group, and 12 players as a continuous training group taken using a purposive sample technique. The exercise is done 3 times a week for 8 weeks. Measurement of VO2 Max uses a Multistage fitness test. Data analysis using the comparative test Wilcoxon Signed Ranks test and Mann Whitney test. Results: The difference between pre-test and post-test in the interval training group was 9.94 while in the continuous training group it was 6.02. Based on the test of the effect of interval training on VO₂ Max, the value of p = 0.008 was obtained and the test of the effect of continuous training on VO₂ Max was obtained p value = 0.005. Based on the different test of the effect of interval training and continuous training on VO₂ Max, the value of p = 0.040 is concluded. Conclusion: interval training and continuous training can increase VO₂ Max. interval training increases VO₂ Max more than continuous training in basketball players in extracurricular curricular students at Senior high school.

The Elevation Training Mask: A Critically Appraised Topic

Clinical Question: Does the elevation training mask (ETM) increase VO2max in healthy individuals who are physically active? Clinical Bottom Line: The current best evidence shows no difference in VO2max improvement compared to training without wearing the ETM while following an exercise program. Several studies demonstrated improvement in measures of respiratory function when wearing the ETM. Further research should investigate changes in physiological variables other than VO2max, specifically those related to respiratory function.

Investigation of the effectiveness of aerobic exercise training in individuals with ankylosing spondylitis: Randomized controlled study

Objective To investigate the effect of the addition of aerobic training to spinal mobility exercises on disease-specific outcomes and functional exercise capacity, aerobic capacity and respiratory muscle strength of ankylosing spondylitis (AS) patients. Methods The study included 31 volunteers (mean age: 44.90 ± 11.52 years) diagnosed with AS. The demographic characteristics and disease-related data of all subjects were recorded, then, the Bath AS Disease Activity Index (BASDAI), Bath AS Metrology Index (BASMI) and Bath AS Disease Function Index (BASFI), the 6-minute walk test, the Bruce Treadmill Test and spirometry were used, respectively. The intervention group attended a 12-week program of aerobic exercise sessions, plus supervised spinal mobility exercises, 3 days a week. The control group performed the supervised spinal mobility exercises only, 3 times a week, for 12 weeks. Results There was a significant improvement in BASDAI (p = .002), BASMI (p = .021), 6 DYT (p = .036), VO2 max (p = .000), MIP (p = .005) and MEP (p = .022) results in the intervention group after 12 weeks of training. In the comparisons of the pre-treatment and post-treatment differences, BASDAI (p = .032) decreased and VO2 (p = .001) max increased, showing significant improvements in the intervention group and these values were maintained. Conclusion It is striking that improvements in all parameters except BASFI were achieved in the aerobic training group. These results demonstrate that an aerobic exercise program should be included in an individual exercise prescription for the management of AS.

Abstract MP14: Lower Cardiovascular Fitness is Associated With Higher C-Reactive-Protein-Related Cardiovascular Risk in Healthy Adolescents and Young Adults

Introduction: Inflammatory markers, such as C-reaction protein (CRP), have been shown to be highly associated with cardiovascular disease. However, it is unclear if baseline levels of cardiovascular fitness in young, healthy persons are related to inflammatory biomarkers who have not yet manifested cardiovascular disease. Methods: Data was compiled from the National Health and Nutrition Examination Survey (NHANES). Cardiovascular fitness level (low, moderate, high) was categorized by estimated VO2 max (with age/sex adjustment cut points). Associations with CRP-based cardiovascular risk were analyzed using ANOVA/Kruskal-Wallis and Chi-squared. Ordered logistic regression was employed to identify predictors of increasing CRP-based cardiovascular risk. To account for the complex survey design, all analyses were conducted using appropriate estimated weights following NHANES analytic guidelines. Results: 2,201 participants from 1999-2004 from ages 12-49 completed cardiovascular fitness testing and had full laboratory analysis. A sensitivity analysis was performed grouping participants into CRP-based cardiovascular risk categories (low &lt;1mg/L, moderate 1-3 mg/L, high &gt;3 mg/L) based on the 2003 AHA/CDC Scientific Statement. Increase in cardiovascular fitness category was associated with decrease in CRP-based cardiovascular risk (OR 0.83, 95% CI 0.75 to 0.91, p&lt;0.001). The relationship was strengthened (OR 0.77, 95% CI 0.68 to 0.87, p&lt;0.001) when adjusting for age, sex, BMI, diabetes, and smoking. Conclusions: In a sample representative of the United States civilian non-institutionalized population, lower levels of cardiovascular fitness were associated with increased inflammatory biomarkers related to cardiovascular risk, even with adjustment for fitness-related covariates. Further studies will help us to understand the therapeutic role on VO2 max and cardiovascular fitness improvement in reducing atherosclerosis-related inflammation.

Effectiveness of High-Intensity Interval Training Versus Moderate-Intensity Continuous Training in Hypertensive Patients: a Systematic Review and Meta-Analysis.

The purpose of this meta-analysis is to compare the effects of moderate-intensity continuous training (MICT) and high-intensity interval training (HIIT) on blood pressure of hypertensive individuals. Continuous aerobic training programs are successful in health promotion and are effective in systolic blood pressure (SBP) and diastolic blood pressure (DBP) modulation. However, HIIT seems to be superior to MICT to improvement of cardiorespiratory fitness. PubMed, ScienceDirect, and Google Scholar were searched for randomized clinical trials that compared chronic effects of HIIT and MICT on BP in hypertensive subjects. Pre- and post-intervention changes in maximal oxygen uptake (VO2max) between MICT and HIIT were analyzed. Both interventions presented significant differences in SBP (MICT: mean difference (MD), 3.7mmHg [95% CI = 2.57, 4.82], p < 0.00001; and HIIT: MD, 5.64mmHg [95% CI = 1.69, 9.52], p = 0.005) and in DBP (MICT: MD, 2.41mmHg [95% CI = 1.09, 3.72], p = 0.0003; and HIIT: MD, 4.8mmHg [95% CI = 2.9, 6.7], p < 0.00001) compared with the control group. No differences were found in the SBP values (MD, 1.13mmHg [95% CI = - 0.01, 2.27], p = 0.05); however, differences were found between groups in DBP (MD, 1.63mmHg [95% CI = 0.83, 2.44], p = 0.0001). In the secondary outcome, both interventions increased VO2max in comparison with control groups (MICT: MD, 1.30ml/kg/min [95% CI = 0.92, 1.68], p < 0.00001; and HIIT: MD, 4.90ml/kg/min [95% CI = 3.77, 6.04], p < 0.00001), and HIIT promoted greater improvement than MICT (MD, 2.52ml/kg/min [95% CI = 1.90, 3.13], p < 0.0001). In conclusion, HIIT and MICT promote reduction in SBP in adults with hypertension, and HIIT showed a greater magnitude in DBP reduction. For hypertensive patients, HIIT may be associated with a greater improvement in VO2max than MICT might.

Circuit resistance training and cardiovascular health in breast cancer survivors.

Cardiovascular disease is the leading cause of death in breast cancer survivors. While evidence shows circuit resistance training (CRT) is effective for improving muscle and cardiorespiratory fitness, whether CRT is an efficacious therapy for decreasing cardiovascular risk in cancer survivors is unclear. Fifty-one breast cancer survivors were recruited to either 12weeks CRT (n=26), or a non-exercising wait-list control (n=25). Two supervised 60min CRT sessions per week were undertaken, comprising resistance and functional exercises, and aerobic exercise stations. Primary outcome measure was the gold-standard assessment of arterial stiffness, aortic pulse wave velocity (PWV). Secondary outcomes included: cardiorespiratory fitness (CRF), upper and lower body strength, arterial wave reflections, central blood pressure and rate pressure product. Compared to the control group, the CRT group had a statistically significant medium effect decrease in PWV 0.9m/s (95% CI: 0.1, 1.7). There were large effect improvements in VO2 max (4.3mlkg-1 min-1 , 95% CI: 5.8, 2.8), upper and lower body strength (3.7kg, 95% CI: 1.9, 5.6 and 10.4kg, 1.6, 19.1) respectively. Findings support the existing literature demonstrating that 12weeks CRT improves muscle and cardiorespiratory fitness and is also an effective strategy for decreasing a proven cardiovascular risk factor in breast cancer survivors.

Effects of Short-Term Green Tea Extract Supplementation on VO2 Max and Inflammatory and Antioxidant Responses of Healthy Young Men in a Hot Environment.

Background:Nowadays, the use of green tea supplements has increased. Studies have shown that green tea can have positive effects on anti-inflammatory and antioxidative factors, as well as improve aerobic performance capacity. Therefore, in this study, we investigate the effects of this supplement on inflammatory factors, total antioxidant capacity responses, and maximum oxygen uptake (VO2 Max) of healthy young men in summer.Methods:This study is a double-blind randomized controlled trial (RCT) in which 15 young men (age 25.06 ± 2.1) were randomly assigned into the green tea (GT) and placebo groups. Subjects performed maximum aerobic exercises (shuttle run 20 m) in separate workouts (14 days) in summer. They consumed 640 mg green tea extracts or maltodextrin 90 min before exercise in a double-blind design. Blood samples were collected before and after the exercise and then evaluated in the biochemistry laboratory. In this study, one way analysis of variance (ANOVA) tests were used for the statistical analysis.Results:The results of this study show that green tea supplement significantly slowed down the increasing tumor necrosis factor alpha (TNF-α) (GT: 15.03 ± 4.31 [pg/ml], placebo: 31.38 ± 7.18 [pg/ml], [P = 0.000]); increased the total antioxidant capacity (GT: 1.04 ± 0.06 [mm], placebo group: 0.72 ± 0.04 [mm], [P = 0.001 VO2]); and Max (GT: 44.43 ± 3.06 [ml/kg/min], placebo group: 34.88 ± 1.30 [ml/kg/min], [P = 0.001]) in the supplement group than placebo. In addition, no significant differences in interleukin 1 beta (IL-1β) was observed between thee groups (GT: 26.86 ± 5.05 [pg/ml], placebo group: 23.47 ± 3.16 [pg/ml], [P = 0.251]).Conclusions:The consumption of green tea supplements 90 min before aerobic exercise may decrease inflammation and oxidative stress factors and improve VO2 Max in summer.

Short-term effects of angiotensin receptor-neprilysin inhibitors on diastolic strain and tissue doppler parameters in heart failure patients with reduced ejection fraction: A pilot trial

ObjectiveAlthough sacubitril/valsartan has recently shown its long-term benefits on morbidity and mortality in symptomatic patients with chronic heart failure with reduced ejection fraction (HFrEF), its short-term effects on diastolic function remain uncertain. We sought to assess 30-day effects of sacubitril/valsartan on left ventricular (LV) diastolic paremeters determined by speckle tracking and tissue Doppler imaging (STI and TDI respectively) as well as their association with functional capacity change evaluated by peak oxygen uptake (VO2max) in stable patients with symptomatic HFrEF. MethodsA total of 35 patients (aged 61 ± 9 years) eligible for sacubitril/valsartan underwent a complete two-dimension (2D) echocardiographic study and a cardiopulmonary exercise test at baseline and 30 days after the initiation of therapy. ResultsSignificant improvements in ratio of trans-mitral inflow early diastolic velocity E to mitral annulus early diastolic velocity E′ (ΔΕ//Ε′ = -35.9%, p = 0.001), peak early diastolic strain rate SRE (ΔSRE = +22.5%, p = 0.024) and ratio E/SRE (ΔE/SRE = -33.2%, p = 0.025) were observed after 1-month therapy. Compared with baseline, VO2max also increased significantly by 16.7 % (p = 0.001). Baseline E/SRE and ΔE/SRE were the strongest independent predictors of VO2max improvement (beta = -0.43, p = 0.004 and beta = 0.45, p = 0.021 respectively) in the multivariate analysis. ConclusionSacubitril/valsartan was associated with early improvement in LV diastolic function determined by TDI and 2D STI. Baseline E/SRE was stronger than standard echocardiographic parameters in predicting the early benefit of sacubitril/valsartan therapy.

Left Ventricular Assist Device Support Complicates the Exercise Physiology of Oxygen Transport and Uptake in Heart Failure.

Low-output forward flow and impaired maximal exercise oxygen uptake (VO2 max) are hallmarks of patients in advanced heart failure. The continuous-flow left ventricular assist device is a cutting-edge therapy proven to increase forward flow, yet this therapy does not yield consistent improvements in VO2 max. The science of how adjustable artificial forward flow impacts the exercise physiology of heart failure and physical O2 transport between the central and peripheral systems is unclear. This review focuses on the exercise physiology of axial continuous-flow left ventricular assist device support and the impact that pump speed has on the interactive convective and diffusive components of whole-body physical O2 transport and VO2.

Improvement of VO2 max in Patient with Restrictive Pulmonary Disorder after Deep Breathing Exercise

Introduction: Restrictive pulmonary disorder is reducing VO2 max values. It can be caused by lung can’t take oxygen from outside air freely. Pulmonary rehabilitation is known to increase the VO2 max. One of the pulmonary rehabilitation is deep breathing exercise. In this study aimed to know the improvement VO2 max after deep breathing exercise. Methods: This was an experimental without control pre and post-experimental study. The Six Minutes Walking Test (6MWT) was measured in patients with restrictive pulmonary disorder, after deep breathing exercise two times a day, for four weeks in May 2018. Results: Fifteen subjects were recruited, with the mean age was 70,76 ± 5,33 years old, 6MWT was 375,13 ± 44,19 m and VO2 Max 31,61±0,86 ml/kg/minute. After four weeks intervention, 6MWT value was 401±44,57 m (p=0.000) and VO2 Max score was 32,11±0,87 ml/kg/minute (p=0.000).

Sex Dimorphism of VO2max Trainability: A Systematic Review and Meta-analysis.

Increases in maximal oxygen uptake (VO2max) are strongly associated with improved cardiovascular health. The aim was to perform a systematic review and meta-analysis to determine whether VO2max responses to endurance training (ET), the most effective intervention to improve VO2max, are influenced by sex. We conducted a systematic search of MEDLINE and Web of Science since their inceptions until February 2019 for articles assessing the VO2max response to a given sex-matched dose of ET in healthy age-matched men and women. Meta-analyses were performed to determine the mean difference between VO2max responses in men versus women. Subgroup and meta-regression analyses were used to assess potential moderating factors. After systematic review, eight studies met the inclusion criteria. All studies implemented common modalities of ET in healthy untrained individuals, comprising a total of 175 men and women (90♂, 85 ♀). ET duration and intensity were sex-matched in all studies. After data pooling, ET induced substantially larger increases in absolute VO2max in men compared with women (mean difference =+191ml·min-1, 95% CI 99, 283; P < 0.001). A greater effect of ET on relative VO2max was also observed in men versus women (mean difference =+1.95ml·min-1·kg-1, 95% CI 0.76, 3.15; P = 0.001). No heterogeneity was detected among studies (I2 = 0%, P ≥ 0.59); the meta-analytical results were robust to potential moderating factors. Pooled evidence demonstrates greater improvements in VO2max in healthy men compared with women in response to a given dose of ET, suggesting the presence of sexual dimorphism in the trainability of aerobic capacity.

Sustained Muscle Deoxygenation vs. Sustained High VO2 During High-Intensity Interval Training in Sprint Canoe-Kayak

Recent data suggests that peripheral adaptations, i.e., the muscle ability to extract and use oxygen, may be a stronger predictor of canoe-kayak sprint performance compared to VO2max or central adaptations. If maximizing the time near VO2max during high-intensity interval training (HIIT) sessions is believed to optimize central adaptations, maximizing the time near maximal levels of muscle desaturation could represent a critical stimulus to optimize peripheral adaptations.Purpose: Therefore, the purpose of this study was to assess the VO2, muscle oxygenation and cardiac output responses to various HIIT sessions, and to determine which type of HIIT elicits the lowest muscle oxygenation and the longest cumulated time at low muscle O2 saturation.Methods: Thirteen well-trained canoe-kayak athletes performed an incremental test to determine VO2max and peak power output (PPO), and 4 HIIT sessions (HIIT-15: 40x[15 s at 115%PPO, 15 s at 30%PPO]; HIIT-30: 20x[30 s at 115%PPO, 30 s at 30%PPO]; HIIT-60: 6x[1 min at 130%PPO, 3 min rest]; sprint interval training (SIT): 6x[30 s all-out, 3 min 30 rest]) on a canoe or kayak ergometer. Portable near-infrared spectroscopy monitors were placed on the Latissimus dorsi (LD), Biceps brachii (BB), and Vastus lateralis (VL) during every session to assess changes in muscle O2 saturation (SmO2, % of physiological range).Results: HIIT-15 and HIIT-30 elicited a longer time >90%VO2max (HIIT-15: 8.1 ± 6.2 min, HIIT-30: 6.8 ± 4.6 min), compared to SIT (1.7 ± 1.3 min, p = 0.006 and p = 0.035) but not HIIT-60 (4.1 ± 1.7 min). SIT and HIIT-60 elicited the lowest SmO2 in the VL (SIT: 0 ± 1%, HIIT-60: 8 ± 9%) compared to HIIT-15 (26 ± 12%, p < 0.001 and p = 0.007) and HIIT-30 (25 ± 12%, p < 0.001 and p = 0.030). SIT produced the longest time at >90% of maximal deoxygenation in all 3 muscles, with effect sizes ranging from small to very large.Conclusions: Short HIIT performed on a canoe/kayak ergometer elicits the longest time near VO2max, potentially conducive to VO2max improvements, but SIT is needed in order to maximize muscle deoxygenation during training, which would potentially conduct to greater peripheral adaptations.